The present invention relates to window blind assemblies and, more particularly, to a blind assembly particularly well adapted for mounting over doorlights.
Window units incorporating blinds are well known in the prior art. These units include two panes of glass an a blind assembly sandwiched between the two panes. The blind assemblies include mechanisms both for raising and lowering the blinds and for tilting the blind slats. The units include slides or knobs or handles coupled to the mechanisms and accessible from the outside of the unit. When a window unit is especially designed or adapted for installation in a door, the unit is referred to as a doorlight.
Because it is difficult, time-consuming and costly to replace existing doorlights with doorlights having integral blinds, retrofit assemblies have been developed for retrofitting blinds over doorlights. These retrofit assemblies include a frame that supports both a pane of glass and a blind assembly. The frame is attached over the frame of the existing doorlight such that the blind assembly is sandwiched between the pane of the assembly and the existing doorlight. Screws are typically used to attach the assembly to the doorlight and/or the door. One particularly good example of a retrofit assembly is illustrated in U.S. Pat. No. 5,996,668 issued Aug. 14, 1998 to DeBlock et al.
Retrofit units are superior to the simple attachment of a blind assembly first because the retrofit units protect the blinds from wear and tear and encase the cords of the blind assembly. Freely hanging cords can be a hazard to children and pets. Second, the retrofit unit confines the blind and prevents the blind from swinging into the door as the door is opened and closed or during high winds, thus preventing damage to the blind and the door. Finally, the encased window blind is more aesthetically pleasing than a traditionally hung window blind; and the encased blind requires cleaning less frequently, if ever.
Despite the advantages of these systems, there is room for improvement. First, the cords in the units can become tangled if the blind is permitted to free fall within the unit and/or if the unit is inverted (e.g. prior to or during installation). Second, the mechanism of the units often are visible along the sides or edges, contributing to an unsightly appearance. Third, the units require a considerable amount of time to install. Fourth, the fasteners for the units leave permanent marks (e.g. holes) in the face of the door, which are unsightly if the retrofit unit is removed. Fifth, stocking of units of blinds having different colors creates a significant inventory issue. Sixth, replacing a blind in a unit is extremely difficult, if not impossible. This can be a problem if a consumer wishes to change the color of the blind assembly or if a defective blind must be replaced. A consumer usually replaces the entire unit if they wish to change the color of the blind.